Can you post a picture? Small is a broad term. If it is buckling due to excessive compressive load on the mast you need a new mast since the entire extrusion has been over stressed. Have the stays been over tightened? Check the mast base as well since all the load is transferred into it. Is it possible the deformation has been there a long time and you just haven't noticed it? Perhaps from whatever was installed in the abandoned holes? If that is the case you may be able to repair or just live with it.